void __trace_hypercall_entry(void)
{
struct cpu_user_regs *regs = guest_cpu_user_regs();
unsigned long args[6];
if ( is_pv_32bit_vcpu(current) )
{
args[0] = regs->ebx;
args[1] = regs->ecx;
args[2] = regs->edx;
args[3] = regs->esi;
args[4] = regs->edi;
args[5] = regs->ebp;
}
else
{
args[0] = regs->rdi;
args[1] = regs->rsi;
args[2] = regs->rdx;
args[3] = regs->r10;
args[4] = regs->r8;
args[5] = regs->r9;
}
__trace_hypercall(TRC_PV_HYPERCALL_V2, regs->eax, args);
}
static void __trace_multicall_call(multicall_entry_t *call)
{
unsigned long args[6];
int i;
for ( i = 0; i < ARRAY_SIZE(args); i++ )
args[i] = call->args[i];
__trace_hypercall(TRC_PV_HYPERCALL_SUBCALL, call->op, args);
}
void pv_hypercall(struct cpu_user_regs *regs)
{
struct vcpu *curr = current;
unsigned long eax;
ASSERT(guest_kernel_mode(curr, regs));
eax = is_pv_32bit_vcpu(curr) ? regs->eax : regs->rax;
BUILD_BUG_ON(ARRAY_SIZE(pv_hypercall_table) >
ARRAY_SIZE(hypercall_args_table));
if ( (eax >= ARRAY_SIZE(pv_hypercall_table)) ||
!pv_hypercall_table[eax].native )
{
regs->rax = -ENOSYS;
return;
}
curr->hcall_preempted = false;
if ( !is_pv_32bit_vcpu(curr) )
{
unsigned long rdi = regs->rdi;
unsigned long rsi = regs->rsi;
unsigned long rdx = regs->rdx;
unsigned long r10 = regs->r10;
unsigned long r8 = regs->r8;
unsigned long r9 = regs->r9;
#ifndef NDEBUG
/* Deliberately corrupt parameter regs not used by this hypercall. */
switch ( hypercall_args_table[eax].native )
{
case 0: rdi = 0xdeadbeefdeadf00dUL;
case 1: rsi = 0xdeadbeefdeadf00dUL;
case 2: rdx = 0xdeadbeefdeadf00dUL;
case 3: r10 = 0xdeadbeefdeadf00dUL;
case 4: r8 = 0xdeadbeefdeadf00dUL;
case 5: r9 = 0xdeadbeefdeadf00dUL;
}
#endif
if ( unlikely(tb_init_done) )
{
unsigned long args[6] = { rdi, rsi, rdx, r10, r8, r9 };
__trace_hypercall(TRC_PV_HYPERCALL_V2, eax, args);
}
regs->rax = pv_hypercall_table[eax].native(rdi, rsi, rdx, r10, r8, r9);
#ifndef NDEBUG
if ( !curr->hcall_preempted )
{
/* Deliberately corrupt parameter regs used by this hypercall. */
switch ( hypercall_args_table[eax].native )
{
case 6: regs->r9 = 0xdeadbeefdeadf00dUL;
case 5: regs->r8 = 0xdeadbeefdeadf00dUL;
case 4: regs->r10 = 0xdeadbeefdeadf00dUL;
case 3: regs->rdx = 0xdeadbeefdeadf00dUL;
case 2: regs->rsi = 0xdeadbeefdeadf00dUL;
case 1: regs->rdi = 0xdeadbeefdeadf00dUL;
}
}
#endif
}
else
{
unsigned int ebx = regs->ebx;
unsigned int ecx = regs->ecx;
unsigned int edx = regs->edx;
unsigned int esi = regs->esi;
unsigned int edi = regs->edi;
unsigned int ebp = regs->ebp;
#ifndef NDEBUG
/* Deliberately corrupt parameter regs not used by this hypercall. */
switch ( hypercall_args_table[eax].compat )
{
case 0: ebx = 0xdeadf00d;
case 1: ecx = 0xdeadf00d;
case 2: edx = 0xdeadf00d;
case 3: esi = 0xdeadf00d;
case 4: edi = 0xdeadf00d;
case 5: ebp = 0xdeadf00d;
}
#endif
if ( unlikely(tb_init_done) )
{
unsigned long args[6] = { ebx, ecx, edx, esi, edi, ebp };
__trace_hypercall(TRC_PV_HYPERCALL_V2, eax, args);
}
curr->hcall_compat = true;
regs->eax = pv_hypercall_table[eax].compat(ebx, ecx, edx, esi, edi, ebp);
curr->hcall_compat = false;
#ifndef NDEBUG
if ( !curr->hcall_preempted )
{
/* Deliberately corrupt parameter regs used by this hypercall. */
switch ( hypercall_args_table[eax].compat )
{
case 6: regs->ebp = 0xdeadf00d;
case 5: regs->edi = 0xdeadf00d;
case 4: regs->esi = 0xdeadf00d;
case 3: regs->edx = 0xdeadf00d;
case 2: regs->ecx = 0xdeadf00d;
case 1: regs->ebx = 0xdeadf00d;
}
}
#endif
}
/*
* PV guests use SYSCALL or INT $0x82 to make a hypercall, both of which
* have trap semantics. If the hypercall has been preempted, rewind the
* instruction pointer to reexecute the instruction.
*/
if ( curr->hcall_preempted )
regs->rip -= 2;
perfc_incr(hypercalls);
}
static void __trace_multicall_call(multicall_entry_t *call)
{
__trace_hypercall(TRC_PV_HYPERCALL_SUBCALL, call->op, call->args);
}